The growth of the internet traffic is causing a corresponding growth in data centers, which employ a large number of servers connected with a network infrastructure. The scalability of current electrical interconnection networks will be soon limited by their power consumption and related power dissipation and footprint issues. In order to overcome these issues optical switching can be exploited, enabling the realization of high capacity and reconfigurable interconnection networks with low power consumption.
To enhance the scalability of the optical interconnection networks, multiple switching domains can be exploited. Multi-plane interconnection networks are composed of a number of transmitter cards and receiver cards, each of them supporting a number of ports, which are optically interconnected. The traditional switching domains used for flexible switching of data packets across all ports and cards are space, wavelength, and time. Space and wavelength domains can be used to switch optical packets among cards and ports respectively, as described in WO2010/127716. Another approach consists of using the space domain to switch packets among cards and time domain to switch among the card ports. This approach requires pulse-width compression (which is a critical process) or by expanding serial packets in the wavelength domain through wavelength-striped techniques.